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Running SVT-VR at lower wattage??

Attenuators == bad idea. You can buy two THD Hot Plates (max rating of 185 each) and figure out some way to parallel things up so all the impedance matches, but it's a bad idea long term. Bad for your amp.


No, it isn't.

Will you wear tubes out quicker? Sort of.

If you were dumping 200W on average into a speaker, and 200W on average into some sort of power soak - the amp won't know the difference (actually probably have an easier time with the more resistive load of the power soak).

Because you have to push more total power to reach the same volume (the entire point of a power soak) - if you're getting the same volume you'll accelerate power tube wear... but it ain't because an attenuator is "bad for your amp", it's because you're running your amp a lot harder.
 
Plain and simple, the VR isn't made for low volume drive. If you've done the relay bypass, your could try using a variac and lower the voltage a bit (but not too much).

Sorry but never a good idea. Doing this drops all the voltage levels in the amp. The heaters will not be as hot, the B+ will drop but worse the bias voltage will drop causing the output stage to draw more current.
 
I do agree with this, no matter what is done will be of detriment to it. But I'd rather run it with lower voltage, than pull tubes on it, if given the choice.


Sorry but never a good idea. Doing this drops all the voltage levels in the amp. The heaters will not be as hot, the B+ will drop but worse the bias voltage will drop causing the output stage to draw more current.
 
I'd MUCH rather run a resistive attenuator than run lower voltage OR pull tubes. They're both much more likely to damage the amp.

An attenuator is damaging as well (transformer in particular). Also finding that attenuator that will handle 300 watts, has yet to be found ;)
 
An attenuator is damaging as well (transformer in particular).

No, it isn't.

An amplifier could care less whether the load it's driving is a pure resistor making heat, or a speaker... well, actually driving a speaker is MORE difficult.

That is unless the physics have changed since I got my Electrical Engineering degree.

Also finding that attenuator that will handle 300 watts, has yet to be found ;)

Huh... this one sitting next to my desk must be a figment of my imagination then...

Apparently you don't know where to look ;)
 
No, it isn't.

An amplifier could care less whether the load it's driving is a pure resistor making heat, or a speaker... well, actually driving a speaker is MORE difficult.

That is unless the physics have changed since I got my Electrical Engineering degree.

Tell this to the many guitarists who have used such devices as the "hot plate" and "powerbrake" and have blown their transformers...

Regardless, If you run your amp hard, with or without an attenuator, weak parts will eventually manifest themselves, but amps tend to run harder with an attenuator, right?......Is this not the purpose?



Huh... this one sitting next to my desk must be a figment of my imagination then...

Apparently you don't know where to look ;)

By Chance, did you make that one? Show me a manufacturer that produces one, for I have not yet found one (that handles 300 watts), nor do I possess Electrical Engineering degree, which would probably aid in the making of one ;)
 
Tell this to the many guitarists who have used such devices as the "hot plate" and "powerbrake" and have blown their transformers...

Regardless, If you run your amp hard, with or without an attenuator, weak parts will eventually manifest themselves, but amps tend to run harder with an attenuator, right?......Is this not the purpose?

Power output is the issue.

If your amp is going to die at 200W - it'll do it whether it's driving 200W into a speaker, or 100W into a speaker and 100W into a resistor.



By Chance, did you make that one? Show me a manufacturer that produces one, for I have not yet found one (that handles 300 watts), nor do I possess Electrical Engineering degree, which would probably aid in the making of one ;)

If you understand Ohms law and how to use a soldering iron - they're pretty darn easy to make. It's not exactly rocket surgery.
 
I used to run two Tom Scholz Power Soaks... one into each 8 Ohm 1x15.

It worked... it cut the volume a bit...

But EVERY single amp tech I told about it TO A MAN said attenuators are a bad idea.

I don't know why... I don't care why.... I just know that all the smart guys I pay to fix the stuff I keep breaking say it's a bad idea, so I don't do it anymore.

I feel your pain, pig.

Start looking for 200 watters.

Fuzz pedals are tinkertoys.
 
If you understand Ohms law and how to use a soldering iron - they're pretty darn easy to make. It's not exactly rocket surgery.

Although I can appreciate your logic with making an attenuator, no thanks :)

Perhaps if it was building an instrument, then It would simplify for me.
 
IMHO If you REALLY want an Attenuator, get one that is good and above 300w.... The SVT may be "300w", but thats 300 clean watts, and it can EASILY surpass that. ;)

Anybody getting my point here?

Just get a 200w amp. Or get two 100w amps. You could probably get what you want with a V4 and some good speaker cabinets.

Buying A smaller amp just makes more sense.

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.... and it gives you a good excuse to buy a bunch of stuff.